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Remains of fetus found in ‘Speed Freak Killers’ grave site

San Joaquin County sheriff's officials say they have found the remains of a fetus in a body dumping site connected to "Speed Freak Killers" Wesley Shermantine and Loren Herzog.

The remains of the fetus, which investigators believe was between 28 and 32 weeks old, were found along with the skeletal remains of three females, authorities said

Victims' remains were found earlier this year after Shermantine provided hand-drawn maps — which he made in his San Quentin prison cell — showing where he and his late childhood friend Herzog dumped their victims during 15 years of thrill-killing.

The men are believed to have killed at least a dozen and as many as 72 people, according to Shermantine. They were dubbed the Speed Freak Killers because they were often high on methamphetamine when they committed their crimes.

In March, forensic scientists used dental records and DNA testing to identify remains found at the site as those of Kimberly Billy, who was 19 when she went missing in 1984, and 16-year-old Joann Hobson, who disappeared in 1985. Both were from East Stockton.

In February, the remains of two other young women who vanished from the Central Valley in the 1980s and '90s were recovered after Shermantine guided investigators to a remote site in Calaveras County. Those remains were identified as Cyndi Vanderheiden, 25, of Clements, and 16-year-old Chevelle "Chevy" Wheeler of Stockton. Vanderheiden went missing in 1998 and Wheeler in 1985.

A third set of skeletal remains has yet to be identified, but forensic anthropologists say they come from a female between 16 and 18.

Shermantine, who was sentenced to death for four murders, provided the directions to bounty hunter Leonard Padilla in exchange for a promise of $33,000 to pay off a restitution order, buy headstones for his parents' graves, and acquire a television and other comforts.

Herzog was originally given a 77-year prison sentence, but it was struck down on appeal and he agreed to a plea deal ahead of a second trial. He was released in 2010 and was living in a trailer near the High Desert State Prison when he got word of Shermantine's cooperation with authorities. Herzog hanged himself in January, a day after learning that any discoveries would probably bring new charges against him and more prison time.